An apparatus has conventionally been proposed which determines whether or not a driver has fallen into an abnormal state where the driver loses an ability to drive a vehicle (for example, a drowsy driving state, a mental and physical failure state, or the like), and performs driving support when the driver is determined to be in such an abnormal state.
For example, one of conventional apparatuses is configured to calculate a deviation ε of a future position from a target course position of a vehicle based on a shape of a traveling road and a position of the vehicle in a traveling lane, to detect a steering angle σ corresponding to a steering operation of the driver, to determine that the driver is in the abnormal state when a region represented by a combination of the deviation ε and the steering angle σ indicates “abnormality”, and to perform driving support such as braking control and the like (for example, refer to Japanese Patent Application Laid-Open (kokai) No. 2009-73462 (see. the abstract, the paragraph [0099], and the like.)